Tuesday, July 18, 2017
The Sky This Week - Thursday July 20 to Thursday July 27
The New Moon is Sunday, July 23. The Moon is at Perigee, closest to the earth, on the 22nd.
Mercury climbs higher in the evening twilight sky. It is now readily visible above the western horizon half an hour after sunset, and is obvious at least 60 minutes after sunset. Mercury is climbing towards the bright star Regulus. On the 25th and 26th Mercury and Regulus will be less than a finger-width apart, on the 25t they are joined by the thin crescent Moon.
Similar views will be seen elsewhere in Australia at the equivalent local time (90 minutes after sunset). (click to embiggen).
Jupiter is rising before sunset and is now high above the northern-western horizon in the early evening at full dark. It is in between the bright star Spica, the brightest star in the constellation of Virgo, and the relatively bright star Porrima. Jupiter is now closer to Porrima than Spica.
Opposition, when Jupiter is biggest and brightest as seen from Earth, was on April the 8th. Jupiter is rising before the sun sets and is visible until just before midnight. Jupiter is a good telescopic target from astronomical twilight on, and the dance of its Moons is visible even in binoculars. The following Jupiter events are in AEST.
Thu 20 Jul 17:53 GRS: Crosses Central Meridian Thu 20 Jul 19:19 Eur: Reappears from Eclipse Thu 20 Jul 21:17 Gan: Disappears into Occultation Tue 20 Jun 22:57 GRS: Crosses Central Meridian Fri 21 Jul 23:40 GRS: Crosses Central Meridian Sat 22 Jul 19:32 GRS: Crosses Central Meridian Mon 24 Jul 18:26 Gan: Shadow Transit Ends Mon 24 Jul 21:11 GRS: Crosses Central Meridian Mon 24 Jul 21:37 Io : Disappears into Occultation Tue 25 Jul 18:49 Io : Transit Begins T Tue 25 Jul 20:02 Io : Shadow Transit Begins ST Tue 25 Jul 21:01 Io : Transit Ends S Tue 25 Jul 22:13 Io : Shadow Transit Ends Tue 25 Jul 22:39 Eur: Transit Begins T Wed 26 Jul 19:32 Io : Reappears from Eclipse Wed 26 Jul 22:50 GRS: Crosses Central Meridian Thu 27 Jul 18:42 GRS: Crosses Central Meridian Thu 27 Jul 21:53 Eur: Reappears from Eclipse
The inset shows the telescopic view of Saturn at this time. Similar views will be seen elsewhere in Australia at the equivalent local time. (click to embiggen).
Saturn was at opposition on the 15th, when it was biggest and brightest in the sky as seen from earth. Saturn is visible all night long. Saturn is a good telescopic target from 9 pm on. It is poised above the dark rifts in the Milky Way and is in a good area for binocular hunting. It continues to climb into the evening skies as the week progresses. Saturn's rings are visible even in small telescopes and are always good to view.
The constellation of Scorpio is a good guide to locating Saturn. The distinctive curl of Scorpio is easy to see above the north-eastern to northern horizon, locate the bright red star, Antares, and the look below that towards the horizon, the next bright object is Saturn.
Similar views will be seen throughout Australia at the equivalent local time (that is 60 minutes before sunrise, click to embiggen).
Venus is lowering in the morning sky and is visible in telescopes as a "Gibbous Moon". At the start of the Week Venus is below the head of Tarus the Bull and the bright star Aldebaran. The Crescent Moon is below Venus on the 21st forming a line with Aldebaran .
Mars is lost in the twilight.
Printable PDF maps of the Eastern sky at 10 pm AEST, Western sky at 10 pm AEST. For further details and more information on what's up in the sky, see Southern Skywatch.
Cloud cover predictions can be found at SkippySky.
Here is the near-real time satellite view of the clouds (day and night) http://satview.bom.gov.au/
Labels: weekly sky